﻿// --------------------------------------------------------------------------------------------------------------------
// <copyright file="DataScalarTaskHelper.cs" company="DHGMS Solutions">
//   Copyright 2004-2014 DHGMS Solutions.
//      
//   Licensed under the Apache License, Version 2.0 (the "License");
//   you may not use this file except in compliance with the License.
//   You may obtain a copy of the License at
//      
//   http://www.apache.org/licenses/LICENSE-2.0
//      
//   Unless required by applicable law or agreed to in writing, software
//   distributed under the License is distributed on an "AS IS" BASIS,
//   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
//   See the License for the specific language governing permissions and
//   limitations under the License.
// </copyright>
// <summary>
//   Defines the DataScalarTaskHelper type.
// </summary>
// --------------------------------------------------------------------------------------------------------------------

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace Dhgms.TplHelper.Model.TaskHelper
{
    using Dhgms.TplHelper.Model.Info;
    using Dhgms.TplHelper.Model.Info.TaskResult;

    public abstract class DataScalarTaskHelper<TDatabaseScalarProducer, TTaskResultClass, TTaskDataType> : InternalTransformerTaskHelper<TTaskResultClass, TTaskDataType>
        where TDatabaseScalarProducer : Model.DatabaseScalarProducer.IDatabaseScalarProducer<TTaskDataType>
        where TTaskResultClass : TaskResultBase, IReportableCount, ITaskDataResult<TTaskDataType>, new()
    {
        protected DataScalarTaskHelper(string name)
            : base(name)
        {
        }

        protected async override Task<DataRetrievalProcessorResult<TTaskDataType>> GetProcessTask()
        {
            var producer = GetProducer();

            var executionResult = await producer.GetResult();

            var result = new DataRetrievalProcessorResult<TTaskDataType>(1, executionResult);
            return result;
        }

        /// <summary>
        /// Gets the producer.
        /// </summary>
        /// <returns>The producer</returns>
        protected abstract TDatabaseScalarProducer GetProducer();
    }
}
